1. Field of the Invention
The present invention relates to an operating apparatus for operating a plurality of control valves which control the operation of a boom cylinder, an arm cylinder, a bucket cylinder and a swing motor of a hydraulic shovel.
2. Description of the Prior Art
A hydraulic shovel is generally constructed as shown in FIG. 6. In FIG. 6, the hydraulic shovel comprises a lower travel body 1, an upper swing body 2, a boom 3, an arm 4 and a bucket 5. These are operated by left and right travel motors (not shown), a swing motor 6, a boom cylinder 7, an arm cylinder 8 and a bucket cylinder 9. Left and right travelling operating levers 11, 12 and left and right operating levers 13, 14 for a work machine are provided in a driver's cab in order to operate the motors 6 and the cylinders 7, 8 and 9.
The hydraulic shovel of this kind are manufactured by several companies. However, the operating pattern thereof, that is, the corresponding relationship between the operating direction of the left and right operating levers 13 and 14 for a work machine and the cylinders 7, 8 and 9 and the swing motor 6 operated thereby differs by makers. Therefore, for example, when an operator familiar with the operating pattern of company A operates the shovel in the operating pattern of the other company, he cannot operate it smoothly due to his non-familiarity with the pattern of that company, thus lowering the work efficiency and resulting in an danger of occurrence of a trouble due to a misoperation.
Incidentally, in the hydraulic shovel, there are four typical operating patterns presently generally used. Therefore, it is desired that in a single machine, several (typically four) operating patterns can be suitably selected by a simple switching operation.
In the past, means for changing the operating patterns known include: